Singletons/PolyKindsApp.hs:(0,0)-(0,0): Splicing declarations
    singletons
      [d| class Cls (a :: k -> Type) where
            fff :: (a :: k -> Type) (b :: k) |]
  ======>
    class Cls (a :: k -> Type) where
      fff :: (a :: k -> Type) (b :: k)
    type FffSym0 = Fff
    class PCls (a :: k -> Type) where
      type Fff :: (a :: k -> Type) (b :: k)
    class SCls (a :: k -> Type) where
      sFff :: Sing (FffSym0 :: (a :: k -> Type) (b :: k))